You're right about things that go missing. As you know, I had to start over from scratch a few months ago so I'm trying to be more careful now. I did a bit of "housekeeping" in my mods folder the other day and realized that I'd removed a few things I shouldn't have and more than once I've deleted my desktop save folder when I'm moving stuff around. So now I check to see whats in my recycle bin before I empty it.
From what I can see, those bugs look like butterflies so if you're infested, I'm happy it's butterflies. It could be worse.